A monitor camera device configured to enable remote control has been used. For example, JP-A-11-243505 discloses a camera system of a superimposed transmission type. In this camera system, a remote control signal is superimposed on a video signal. The camera and the rotary base thereof are remote controlled according to the remote control signal.
FIG. 6 shows an example of the configuration of a monitor camera device in the related art. A monitor camera device 100 comprises a camera 102, a lens 104, a rotary base 106, a rotary base receiver 108, a coaxial cable 110, a system controller (control device) 112, and a TV monitor 114. The rotary base receiver 108 is provided to the rotary base 106, and it controls the rotary base 106 and the lens 104 (zoom lens or the like). The camera 102, the rotary base receiver 108, and the system controller 112 are cascade connected via the coaxial cable 110. A video signal from the camera 102 is supplied to the system controller 112 via the rotary base receiver 108.
A remote control signal is superimposed on a video signal and transmitted via the coaxial cable 110. In remote control, the system controller 112 side is the master device of operations. The camera 102 and the rotary base 106 are independent slave devices. A command to camera and a command to rotary base are transmitted as the remote control signal. The camera 102 performs its own operation upon receipt of a command to camera. Also, the rotary base receiver 108 and the rotary base 106 perform their own operations upon receipt of a command to rotary base.
In the configuration in the related art, power is also supplied to the camera side from the system controller 112 via the coaxial cable 110.
In the monitor camera device in the related art, however, in a case where a serial communication, such as RS485, is made available, or in a case where the monitor camera device is controlled using the IP protocol communication, such as Ethernet (registered trademark) and a telephone line, the circuit configuration for a superimposed transmission can no longer be used. Hence, the system configuration has to be changed considerably.
In addition, when the protocol communication described above or the like is made, respective devices (the camera and the rotary base receiver in the case above) need to have individual physical addresses as the destinations of control. This makes the control complicated. In particular, because a host authentication is required for each IP address in the IP network, each of the camera and the rotary base control device needs respective processing.